Drums or related percussion instruments can be difficult to tune. For example, the fundamental frequency of a two-headed drum can be varied by adjusting either the top or bottom heads, resulting in an infinite number of drumhead frequency combinations for a given fundamental frequency.
One important requirement with respect to drum tuning is for each drumhead to be tuned uniformly, that is, to produce the same frequency when tapped near each tuning lug near the edge. Another requirement is for the drum to have the desired fundamental frequency when tapped near the center. A third requirement is to maintain a specific frequency relationship between top and bottom heads in order to control other aspects of the drum sound so it is preferable to raise or lower the frequency of both heads to adjust the fundamental frequency. However, it is time-consuming to tune a drumhead uniformly. Even after both drumheads are in tune with themselves, i.e., tuned uniformly, the resulting fundamental frequency may be inadequate or incorrect. If so, then one or both heads must typically be re-adjusted until the desired fundamental frequency is achieved. Conventional tuning techniques consequently entail a time-consuming trial and error process.